In the terminology of organ building, a flue pipe in which the end remote from the mouth is closed by a movable stopper or airtight cap. This provides a means of tuning.
In general, a stopped pipe is any tube that communicates freely with the ambient air at one end and is completely closed at the other. The Air column in such a tube will vibrate with an antinode at the open end and a node at the closure. The fundamental is approximately an octave lower than that given by a pipe of equal dimensions open at both ends, and its wavelength is four times that of the tube itself. The harmonic series of a stopped pipe lacks the even-numbered partials; Overblowing begins a 12th above the fundamental. Because it shows this characteristic the clarinet is sometimes loosely termed a stopped pipe. Among folk instruments the stopped pipe is represented by many end-blown flutes of varying degrees of sophistication.
PHILIP BATE